Learn Swift-arrays (array)-Continuous updates

collection type--array

Array is a collection type in swift: arrays, which store multiple values of the same type using an ordered list, the biggest difference from the nsarray of OC is thatSwift's array is a value type, and an array of OC is a reference type

methods for declaring arrays

If declaring a mutable array is set to a variable var somemutablearray = [Int] ()  //declares an empty array of type int//the opposite declares an immutable variable set as constant let Somearray = Array (Count:5, Rep eatedvalue:0.03)    //declares an immutable group, the type custom inference is a double type, contains 5 elements, their values are 0.03//the declaration method of the directly set element let Someint = [3,5,8,10,91]// Declares an array that can contain any type var array = [any] ()

accessing an element or other property in an array

Let someint = [3,5,8,10,91]someint.first   //takes the first element of the array, if the array is empty return nilsomeint.last    //Take to the last element of the array, if the array is empty return Nilsomeint.count   //Get the number of elements in the array someint.isempty//Determine if the array is empty return truesomeint[4]//The      value of the 4th element is accessed through the subscript script, Note that the subscript is calculated from 0 let subints = someint[2...4]  //The element is accessed through a range, returning an array

Add a new element to an array

var somemutablearray = [Int] ()  //declares an empty array type of intsomemutablearray.append (5)      //Add an element 5someMutableArray + = [11, 0]     //Splicing An array Somemutablearray.insert (3, atindex:1)  //Insert a value in the specified subscript

Delete Elements of an array

var Somemutablearray = [5, ten, A, a, a, A, 411]somemutablearray.removelast ()   // Delete last element Somemutablearray.removefirst ()  //Delete First element Somemutablearray.removerange (0...2)// Delete a range of elements somemutablearray.removeatindex (0)   //Delete the element at the specified position somemutablearray.removeall ()        //Delete all elements

to modify an element in an array

var someint = [[1, 2, 3]/(+, +, 558]someint[5] = 111            //Modified by subscript script someint[0...2]  

Common traversal methods

var someint = [[+], +, +, +, +, +, 558]for item in Someint {    print (item)//item automatically infers type}for (index, value) in some Int.enumerate () {    //traversal through a tuple, index is subscript, value is    print (index, value)}

Learn Swift-arrays (array)-Continuous updates